The present invention relates to an improved golf club shaft grip.
It is well known that shock generated by impact between a golf club and a golf ball can adversely affect muscle tissue and arm joints such as elbow joints. The energy generated by such shock is usually of high frequency and short duration with rapid decay, and which is often known as xe2x80x9cimpact shock.xe2x80x9d Tight grasping of a grip to keep it from slipping contributes to the shock to the muscle tissue and arm joints of the users golf clubs.
Prior art golf club shaft grips have utilized a layer of polyurethane backed with a layer of felt. In general, the felt layer has a thickness of about 1.40 mm. The polyurethane layer is generally thinner than 0.25, and has been considered only as providing tackiness, i.e., resistance to the slip caused by a sweaty hand. The polyurethane has not been considered to be useful for inhibiting shock. The felt was relied upon to cushion the user""s arm and hand against the shock created when the club strikes the ball.
Applicant has previously developed resilient grips which successfully reduce shock to the muscle and arm joints of the users of golf clubs, tennis racquets, racquet ball racquets, baseball bats, and other impact imparting devices such as hammers. See, for example, U.S. Pat. No. 5,374,059 granted to applicant Dec. 20, 1994. Such earlier grips utilize a polyurethane layer bonded to a felt layer to define a strip which is spirally wrapped around the handle of a golf club or racquet to conform to the external configuration of such handle. In such earlier grips of applicant""s design the thickness of polyurethane layer relative to the thickness of the felt layer as compared to prior art resilient grips, i.e. the ratio of the thickness of the polyurethane layer to the thickness of the felt layer was a minimum of approximately 0.18, with the thickness of the polyurethane layer hag been about equal to or thicker than the thickness of the textile layer in a typical grip of my design. In certain of such grips the handle-abutting side of the strip utilized skiving, with the felt layer tapering from a transverse central region upwardly and outwardly towards the transverse side edges of the strip. The side edges of the strip are overlapped as the strip was wrapped around the shaft so that the strip did not have a smooth configuration along its length. Additionally, the skiving tended to weaken the grip. Moreover, the side edges of the strip tended to unravel in use. It was also determined that where the strip was not properly applied to the shaft, the grip would tend to loosen relative to the shaft. Likewise, prior golf club grips employed caps which failed to adequately prevent unraveling of the grip from the golf club shaft.
Applicant has discovered that polyurethane and felt golf club shaft grips of the aforedescribed nature can be made without skiving to thereby afford a stronger, longer lasting grip. Instead, in the grip of the present invention the side edges of the strip are butted together as the strip is wrapped about the golf club shaft. The resulting grip provides a smoother configuration over the entire grip surface and also resists unraveling from the shaft. The improved grip of the present invention also incorporates an adhesive material that covers the inner surface of the felt layer to facilitate wrapping the strip about the golf club shaft and afford increased securement of the grip to the shaft as the grip is used, with the tighter the grasp of the player the tighter the securement of the grip to the shaft. The grip of the present invention additionally reduces the manufacturing time and therefore the cost of the grip to the user as compared to prior grips. Moreover, it is easier to properly wrap the strip onto the shaft so that even an amateur can obtain a firm attachment of a replacement grip to the shaft.
The grip of the present invention also preferably utilizes sidewardly and outwardly curved reinforcement side edges along its length. Such side reinforcement edges inhibit unraveling of the grip from the golf club shaft, enhances the frictional grip of the user and provides an improved appearance over existing grips. This feature also reduces interference with other golf club grips as club is withdrawn from a golfer""s bag. The grip of the present invention may either be used to as a replacement grip, or, alternatively be fabricated as original equipment by a manufacturer of golf clubs. The grip may include a tapered rubber-like sleeve about which the strip is spirally wrapped, or the strip may be spirally wrapped directly upon the handle portion of golf club shaft.
It is an important feature of the grip of the present invention mat the grip includes a unique cap which cooperates with the spirally wound strip to prevent unraveling of the strip from the golf club shaft both during play, and more importantly as a golf club is withdraw from and returned to a golfer""s bag.
The golf club grip of the present invention has been found to greatly cushion the shock transferred from a golf club to the golfer""s body and thereby prevent me danger of injury to the golfer during a golf swing. Yet me golf club grip of the present invention can be made lighter than conventional grips to reduce me grip weight of a golf club permitting redistributing me weight to me golf club head thereby increasing me moment of inertia with a resulting increase in me distance of travel of a golf ball. The golf club grip of me present invention can also reduce me total weight of a golf club and thereby permits a higher club head speed for greater distance of travel of a golf ball.
These and other features and advantages of the present invention will become apparent from the following detailed description, when taken in conjunction with the accompanying drawings.